Yes, that's how I knitted for the first 3 years... then (age 12) I went to a friend's mother to get some help.
The 13-year-old daughter came in and saw me sitting there with the one needle sticking up between my legs and...
"Oh, Mama!! LOOK at how she's holding that!"
"Yes, Bonnie. Be quiet, honey."
"But MAMA! LOOOK at it!!!"
I hadn't the vaguest idea what was going on, but I decided I'd better teach myself to hold BOTH needles in BOTH hands.
Years later, I finally figured out why Bonnie got so freaked....